Veneer slicer machine

ABSTRACT

A veneer slicing machine or wood shearing machine includes a supporting table for receiving the wood stock to be cut which is indexed upwardly at a predetermined rate in dependence upon the wood sheets or veneer which is to be formed. The block is cut by a movable knife blade assembly which is mounted at each end on slide members which move backwardly and forwardly on defined trackways on each side of a machine frame. A smaller stroke and less stress operation of the machine is obtained by driving the knife assembly through a drive motor connected to separate rotatable fly wheels. The fly wheels are connected through respective connecting rods which are articulated to their periphery and to the blade assembly at their respective opposite ends at locations adjacent each end of the assembly. A third connecting rod is pivoted at its one end to the frame of the machine and pivoted at its opposite end to the blade assembly adjacent one of the pivot rod connections. It&#39;&#39;s end which is connected to the blade assembly moves through an arc, and the combined motion is such that the blade approaches the wood stock when it is angled transversely by an angle of 5* and this angle will vary, until it reaches the end of the shearing operation, to a value of about 20*. In an alternate arrangement the table, or bed carrying the wood stock, is connected to the fly wheels for movement backwardly and forwardly along with the shearing knife to provide a divided stroke system which will have smaller dynamic stresses than the fixed system.

Unite States Patent n91 Cremona Aug. 7, 1973 VENEER SLICER MACHINE [76]Inventor: Angelo Cremona, Viale Lombardia 275, 20052 Monza, Italy [22]Filed: Nov. 24, 1971 21 Appl. No; 201,846

Related U.S. Application Data [63] Continuation-in-part of Ser. No.106,646, Jan. 15,

1971, abandoned.

Primary Examiner-Andrew R. Juhasz Assistant Examiner-W. Donald BrayAtt0rney.lohn J. McGlew et a1.

[57] ABSTRACT A veneer slicing machine or wood shearing machine includesa supporting table for receiving the wood stock to be cut which isindexed upwardly at a predetermined rate in dependence upon the woodsheets or veneer which is to be formed. The block is cut by a movableknife blade assembly which is mounted at each end on slide members whichmove backwardly and forwardly on defined trackways on each side of amachine frame. A smaller stroke and less stress operation of the machineis obtained by driving the knife assembly through a drive motorconnected to separate rotatable fly wheels. The fly wheels are connectedthrough respective connecting rods which are articulated to theirperiphery and to the blade assembly at their respective opposite ends atlocations adjacent each end of the assembly. A third connecting rod ispivoted at its one end to the frame of the machine and pivoted at itsopposite end to the blade assembly adjacent one of the pivot rodconnections. lts end which is connected to the blade assembly movesthrough an arc, and the combined motion is such that the bladeapproaches the wood stock when it is angled transversely by an angle of5 and this angle will vary, until it reaches the end of the shearingoperation, to a value of about 20. in an alternate arrangement thetable, or bed carrying the wood stock, is connected to the fly wheelsfor movement backwardly and forwardly along with the shearing knife toprovide a divided stroke system which will have smaller dynamic stressesthan the fixed systern.

5 Claims, 5 Drawing Figures VENEER SLICER MACHINE REFERENCE TO OTHERPATENT APPLICATION This application is a continuation-in-part ofapplication Ser. No. 106,646 filed Jan. 15, 197], by the same inventoras the present case and now abandoned.

BACKGROUND OF THE INVENTION 1. Field of the Invention This inventionrelates in general to devices for cutting thin strips from a wood log orstock of wood and in particular to a new and useful veneer slicer havinga shearing blade assembly which is mounted for sliding movementbackwardly and forwardly over the wood stock as the stock is advancedtoward the shear in incremental steps and which is driven in a manner tochange its transverse angle of approach to the wood stock during theshearing operation.

2. Description of the Prior Art At the present time veneer slicermachines are known which include a shearing knife which is movable overa wood workpiece in order to effect thin shearing cuts of the wood toform veneer. Such devices include knife blade assemblies which arecarried on slides which move on trackways at each end of the blade andthe assembly may be moved so that the knife blade is at an angle inrespect to the wood block which is being cut. Such oblique cutting iscarried out in order to lower the shearing stresses during theoperation. This is obtained by either orienting the blade at an angle tothe machine axis or by angling the wood stock relative to the blade. Inboth methods the shearing stroke is relatively large and this is afunction of the angle which is established between the blade and thewood stock.

SUMMARY OF THE INVENTION In accordance with the invention a woodshearing apparatus includes a movable blade assembly which is driven bymeans to control the shearing angle in re spect to the wood stock in amanner to lower the stress operation of the machine and to permit themovement of the blade through smaller strokes. The drive includeslaterally spaced rotating fly wheels which are connected to the movingblade through separate connecting rods which have their one ends pivotedto the periphery of the fly wheels and the opposite ends pivoted torespective ends of the movable knife. The knife assembly is furthercontrolled by means of a connecting rod which is pivoted at one end to-afixed location of the frame between the fly wheels and pivoted at itsopposite end to the movable knife assembly at a closely spaced locationin respect to one of the connecting rods. The individual connecting rodswhich are secured to the fly wheels are arranged in parallelrelationship and are of the same length and they move in the form of aparallelogram during the motion of the knife blade assembly.

In accordance with another embodiment of the invention the table or bedwhich carries the wood stock is connected to the fly wheels throughconnecting rods arranged at each end and in a parallel relationship toeach other so that there is a combined'movement of the wood and theblade so that still further reductions in shearing stress and length ofstroke may be accomplished.

Accordingly it is an object of the invention to provide an improveddevice for cutting wood veneer which includes a drive for a movableknife blade with a controlled movement of the blade past a wood supplyor stock to cut the stock into veneer strips and which includes meansfor orienting the blade so that the approach in respect to the woodstock is controlled during the cutting movement to provide an optimumshearing action, lower cutting stroke length and a reduction of shearingstresses.

A further object of the invention is to provide a drive mechanism foroperating a shearing knife assembly in respect to a wood stock supportedadjacent the assembly and advanced in relation to the assembly inaccordance with the thickness to be cut during each working stroke, andwhich includes laterally spaced rotating fly wheels which are connectedthrough substantially parallely arranged connecting rods to respectiveends of the knife blade assembly, and which is also connected by meansof a connecting rod which is articulated at a fixed point and to one endof the assembly adjacent the connection of one of the connecting rods.

A further object of the invention is to provide a veneer slicer in whichthe shearing blade is moved through a varying angle in respect to thewood stock to be cut, and in which the wood stock is held either in afixed location and advanced in increments toward the blades during eachsuccessive stroke or is held on a movable bed which is also drivenbackwardly and forwardly along with the shearing knife.

The various features of novelty which characterize the invention arepointed out with particularity in the claims annexed to and forming apart of this disclosure. For a better understanding of the invention,its operating advantages and specific objects attained by its uses,reference should be had to the accompanying drawing and descriptivematter in which there is illustrated preferred embodiments of theinvention.

BRIEF DESCRIPTION OF THE DRAWING In the drawing: FIG. 1 is a schematictop plan view of a veneer slicer constructed in accordance with theinvention;

FIG. 2 is a section taken along the line 2-2 of FIG. 1; FIG. 3 is a viewsimilar to FIG. 1 of another embodiment of the invention;

FIG. 4 is a section taken along the line 44 of FIG. 3;

FIG. 5 is a section taken along the line 55 of FIG.

GENERAL DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to thedrawings in particular the invention embodied therein in FIGS. 1 and 2comprises a veneer slicer which includes a machine base or frame 10having a bed or table 12 carrying a wood stock for a workpiece 15 whichis advanced with the table 12 after each successive shearing or cuttingstroke of a cutting blade or knife assembly generally designated 14. Theadvancing of the table 12 is, for example, carried out by the rotationof a threaded spindle 18 which engages with a nut 20 affixed to thetable 12 after each operation stroke by an amount which is set by theselection of the veneer thickness to be formed. The wood stock carriedon the table is indexed to the value of the desired sheet thickness withevery knife stroke and the table may, for example, be supported by aplurality of the threaded spindles 18 which is connected to a selectiondevice, (not shown), which controls the indexing of the table and hencethe thickness of the veneer which is cut.

in accordance with the invention the knife blade assembly 14 issupported at each end on respective slide members 22 and 24 which ridein trackways 26 and 28 defined at each side of the machine frame 10. Theknife assembly 14 and the slides 22 and 24 connected thereto slide onthe trackways 26 and 28 of the machine frame during the feeding phase orcutting phase while during its reversal phase the wood stock is liftedby the table in accordance with the thickness of the next sheet to becut. The movable knife assembly 14 is driven by drive means whichincludes a drive motor 30 which is connected, for example, through apulley 32 to a variable speed coupling 34 on a split drive shaft 36. Thesplit drive shaft carries worms 38 and 40 at respective ends whichengage with and rotate gears 42 and 44 respectively which are secured byrespective shafts 46 and 46' which carry fly wheels 50 and 52respectively.

In accordance with a feature of the invention the fly wheels 50 and 52are connected through parallelly arranged connecting rods 54 and 56respectively to the knife assembly 14. The connecting rods 54 and 56 arepivoted at 58 and 60 to respective ends of the knife blade assembly 14.In addition, a third connecting rod 66 is pivoted at its one end on apivot 68 carried on a fixed bracket 70 and pivoted at its opposite endto a pivot 72 which is spaced closely to the pivot 60 on the cuttingblade assembly 14. The pivot point 72 moves through an arcuate path 74as shown in FIG. 1.

During operation the blade assembly 14 is forced to advance with theblade edge normal to the longitudinal axis X-X of the machine butlaterally angled or obliquely in respect to the wood stock 15. In orderto favor this movement an enlargement of the trackways 26 and 28 toaccommodate the slides 22 and 24 is provided. The connecting rod 66 mayact as a strut as well as a tie rod. It should be appreciated that thewood stock 15, as shown in the drawings, is arranged obliquely but thisinclination is in fact very small and is shown exaggerated in thedrawings. In practice it is necessary to impart only a few degrees oflateral inclination to the wood stock so as to avoid the attacking of awood stock by the blade throughout its length simultaneously.

The connecting rods 54 and 56 areof the same length and they form partof an articulated parallelogram which moves as a function of the pivotalconnection of the associated connecting rods to the fly wheels 42 and 44as the fly wheels are rotated. The location of the pivot 68 and 72 forthe connecting rod 66 determine the path of the curve of the bladeholder assembly 14 and the position of the arcuate path 74 and theconstruction is such that during a complete stroke move ment of theknife blade assembly 14 from the rear dead center to the front deadcenter, the position of the blade will be displaced in respect to itsangle to the center line X-X of the machine so that it becomes inclinedin respect to the wood stock by an initial amount of 5 which varies upto about a value of before the end of the shearing operation.

A preferred embodiment of the device is shown in FIG. 3 to 5, whereinsimilar parts are similarly designated but with primes added. Theconstruction shown in FIGS. 3 to 5 provides a drive means for moving thebed 12 for the wood stock 15' during the cutting operation so that thestroke of movement of the combined movement of the blade assembly 14'and the bed 12' will be of a lesser magnitude. This construction alsoreduces the stresses at the dead center locations and provides amovement of the bed 12 and the blade holder assembly 14' insubstantially a straight line but with the blade shifted angularly inrespect to the wood stock 15'. The drive connections for the bladeassembly 14'.

are similar to that of the other embodiment but in this embodiment anadditional connecting rod 80 is pivoted at 72' to the blade assembly 14'and at 68' to a bracket but it includes an extension portion a which ispivoted on a bracket 82 at a pivot location 84.

The drive means also includes a connecting rod 86 and 88 which iseccentrically connected at 90 and 92 respectively to the fly wheels 50'and 52' respectively, and at their opposite ends are connected to thebed 12 at 90 and 92 respectively.

While specific embodiments of the invention have been shown anddescribed in detail to illustrate the application of the principles ofthe invention, it will be understood that the invention may be embodiedotherwise without departing from such principles.

What is claimed is:

l. A device for cutting wood stockinto thin sheets, particularly forslicing wood veneer, comprising a machine frame, a cutting bladeassembly guided for back and forth movement on said frame, bed holdingmeans for holding the wood stock adjacent said cutting blade assembly ina position to be cut thereby, and a drive for said cutting bladeassembly to move it into cutting engagement with the wood stock at anangle in respect to the wood stock which varies during the cutting and,including first and second spaced fly wheels rotatably mounted on saidmachine frame, means to rotate said first and second fly wheels, firstand second parallelly arranged connecting rods pivoted at their one endto said fly wheels eccentrically in respect to the axis thereof, and attheir opposite ends to respective spaced longitudinal locations on saidcutting blade assembly, and a third connecting rod having one endpivotally connected to said machine frame and an' opposite end pivotallyconnected to said cutting blade assembly at a location closer to one ofsaid connecting rods and to the other of said first and secondconnecting rods, said drive including means for moving said bed holdingmeans for the wood stock backwardly and forwardly along with saidcutting blade.

2. A device according to claim 1, wherein said first and second flywheels includes a shaft having a gear thereon, a rotatable drive shafthaving a worm at respective opposite ends connected to the gears of saidfly wheel shaft for rotating said fly wheels.

3. A device according to claim 1, wherein said first and secondconnecting rods are of equal length.

4. A device according to claim 1, including means for advancing said bedholding means to index the wood stock into the cutting plane by anamount corresponding to the thickness to be cutoff from the wood stock.

5. A device according to claim 1, wherein said means for moving said bedholding means comprises first and second bed connecting rods havingtheir one ends eccentrically connected to said fly wheels and theopposite ends pivotally connected to said bed holding means atlongitudinally spaced locations.

1. A device for cutting wood stock into thin sheets, particularly forslicing wood veneer, comprising a machine frame, a cutting bladeassembly guided for back and forth movement on said frame, bed holdingmeans for holding the wood stock adjacent said cutting blade assembly ina position to be cut thereby, and a drive for said cutting bladeassembly to move it into cutting engagement with the wood stock at anangle in respect to the wood stock which varies during the cutting and,including first and second spaced fly wheels rotatably mounted on saidmachine frame, means to rotate said first and second fly wheels, firstand second parallelly arranged connecting rods pivoted at their one endto said fly wheels eccentrically in respect to the axis thereof, and attheir opposite ends to respective spaced longitudinal locations on saidcutting blade assembly, and a third connecting rod having one endpivotally connected to said machine frame and an opposite end pivotallyconnected to said cutting blade assembly at a location closer to one ofsaid connecting rods and to the other of said first and secondconnecting rods, said drive including means for moving said bed holdingmeans for the wood stock backwardly and forwardly along with saidcutting blade.
 2. A device according to claim 1, wherein said first andsecond fly wheels includes a shaft having a gear thereon, a rotatabledrive shaft having a worm at respective opposite ends connected to thegears of said fly wheel shaft for rotating said fly wheels.
 3. A deviceaccording to claim 1, wherein said first and second connecting rods areof equal length.
 4. A device according to claim 1, including means foradvancing said bed holding means to index the wood stock into thecutting plane by an amount corresponding to the thickness to be cutofffrom the wood stock.
 5. A device according to claim 1, wherein saidmeans for moving said bed holding means comprises first and second bedconnecting rods having their one ends eccentrically connected to saidfly wheels and the opposite ends pivotally connected to said bed holdingmeans at longitudinally spaced locations.